Human MDA-MB-435 is a cell line isolated from the pleural effusion of a 31 year old female with metastatic, ductal adenocarcinoma of the breast. GFP-expressing MDA-MB-435 (GFP-MDA-MB-435) are selected from MDA-MB-435 cells after infected with lentiviruses expressing GFP with puromycin. The cells are shipped in a frozen vial with more than 5 x 105 cells/vial. Universal Full Growth Medium is recommended for cell culture and these cells have an average minimum population doubling levels ; 20 when cultured following the detailed protocol described below.